ABSTRACT
Objective To study the effect of different concentrations of fluoride on cultured human umbilical vein vascular endothelial cells(HUVEC). Methods Different doses of sodium fluoride (NaF) were added to HUVEC culture medium, fluoride concentrations were 0(control), 100,400,700,1000,2000 μmol/L, respectively,6 re-set hole in each group. After continuous culture for 48 h, cells and culture medium were collected. Cell morphology was studied by Wright-Giemsa staining; cells apoptosis was determined by acridine orange fluorescence staining; cell activity was measured by methyl thiazolyl tetrazolium (MTT) assay; superoxide dismutase (SOD),glutathione peroxidase(GSH-Px) activity, malonaldehyde(MDA) content, induced nitricoxide synthase(iNOS), and endothelia nitricoxide synthase(eNOS) activity in cell culture medium were determined by spectrophotometry; cell iNOS mRNA and eNOS mRNA expression were detected by RT-PCR; intercellular adhesion molecule-1 (ICAM-1)and vascular cell adhesion molecule-1 (VCAM-1) levels were detected by double antibody sandwich ELISA method.Results With increased dose of fluoride, HUVEC cells decreased, the structure changed. In 400 - 2000 μmol/L group, the SOD activity[(6.627 ± 0.213), (6.668 ± 0.152), (5.935 ± 0.122), (4.755 ± 0.182)kU/L] was lower than those of the control group[(7.457 ± 0.398)kU/L, P ＜ 0.05 or ＜ 0.01], GSH-Px activity[(481.284 ± 43.785),(492.223 ± 16.474), (382.762 ± 25.167), (293.687 ± 24.881 )kU/L] was also lower than those of the control group [(585.078 ± 47.323)kU/L, P ＜ 0.05 or ＜ 0.01], MDA level[(0.609 ± 0.011 ), (0.646 ± 0.016), (0.852 ± 0.013),(1.188 ± 0.045)nmol/L] was higher than those of the control group[(0.512 ± 0.027)nmol/L, P ＜ 0.05 or ＜ 0.01];iNOS activity[(3.604 ± 0.115), (3.615 ± 0.075), (3.848 ± 0.103), (4.275 ± 0.079)kU/L] also was higher than those of the control group[(2.798 ± 0. 136)kU/L, all P ＜ 0.01], iNOS mRNA expression increased, eNOS activity [(5.539 ± 0.079), (5.503 ± 0.064), (5.226 ± 0.142), (4.809 ± 0. 107)kU/L] decreased compared to those of control group[(5.996 ± 0.155)kU/L, P ＜ 0.05 or ＜ 0.01], eNOS mRNA expression decreased; ICAM-1 levels [(0.852 ± 0. 102), (0.886 ± 0.061 ), (0.961 ± 0.158), (1.418 ± 0. 167)μg/L] increased compared to those of the control group[(0.687 ± 0.046)μg/L, P ＜ 0.05 or ＜ 0.01], VCAM-1 levels[(2.719 ± 0.197), (2.946 ± 0.167),(3.173 ± 0.225 ), (3.613 ± 0. 153 ) μg/L] was higher than those of the control group [(2.375 ± 0.067 ) μg/L, all P ＜0.01]. Conclusions High concentrations of fluoride reduce the activity of antioxidant enzymes, which leads to metabolic disorders of nitric oxide and abnormal cytokines expression, thereby inhibiting vascular endothelial cell growth, structural change and induced apoptosis. This is an important factor in high fluoride-induced vascular endothelial injury.
ABSTRACT
Objective To knowthe effect of selenium on expression ofnitric oxide synthase(eNOS) and inducible nitric oxide synthase(iNOS) induced by fluoride in ECV-304(human umbilical vein endothelial cells).Methods The cells,ECV-304,were divided into two groups and treated as follows,one group was treated with sodium fluoride at different doses(0,400,1 000 and 2 000 ?mol/L),the other was treated with sodium fluoride at different doses(0,400,1 000 and 2 000 ?mol/L)and added sodiumselenite(100 nmol/L) respectively.24 h of treatment,The activity ofeNOS and iNOS were measured by NO and NOS assay kits and the expression of eNOS mRNA and iNOS mRNA was analyzed by RT-PCR.Results The activity of eNOS and the expression of eNOS mRNA were down-regulated by fluoride with a dose dependent manner,while the activity of iNOS and the expression of iNOS mRNA were up-regulated.Selenium showed a significant antagonism to low level fluoride treated groups.Conclusion Seleniumcan antagonize the effect offluoride on the expression ofiNOSand eNOS in the vein endothelial cells when the fluoride exposure level is not toohigh.